Locks have been used for securing gates and doors throughout most of recorded history. The oldest known lock is approximately 4,000 years old and dates to ancient Egypt. The earliest known key-based lock was built during the Assyrian Empire in Khorsabad near Nineveh in about 704 BC, and used the same pin-tumbler principle that is still employed by many modern locks. Although modern locks are far more sophisticated than their early predecessors, they nevertheless perform substantially the same function of controlling access to a secure area. In particular, access to the secure area is prevented until the lock is released using a physical object such as for instance a key, a keycard, a fingerprint, a RFID card or a security token, or by presenting secret information such as for instance a key-code or a password, etc.
Today, a lock may be either mechanical or electronic. Electronic locks may be stand-alone, with an electronic control assembly mounted directly to the lock, but more commonly electronic locks are connected to an access control system. Typical components of an access control system include a reader, a controller, a door contact and a request-to-exit device. However, it is to be understood that not all of these components are present in all access control systems and that some systems may include additional components. The reader is disposed on a secured side of a doorway, and is used for reading a token that is carried by an authorized individual. For instance, the reader is a radio frequency identification (RFID) tag reader that is capable of interrogating a RFID tag embedded within a card that is carried by the authorized individual. The reader sends a signal to the controller, based on a result of the interrogation, and the controller uses this signal to determine whether or not to unlock the door. Similarly, the door contact is in communication with the controller for providing a signal thereto when the door is opened—known as an event. In order to avoid logging an event every time someone exits through the doorway, it is common practice to provide a request-to-exit device on the non-secured side of the door. The request-to-exit device is typically a button or a motion sensor, and it is activated prior to an individual exiting through the doorway so that when the door is subsequently opened the system does not interpret this as a forced-door event.
In a traditional access control system the controller is disposed in an electrical room, and the readers, locks, door contacts and request-to-exit devices that are installed at each door are all wired back to the controller. Different controllers are used to control different groups of doors, and these controllers also communicate over a network with a central server or with a similar processing unit. Unfortunately, in this type of system it is necessary to install multiple runs of cable from each doorway to the controller in the electrical room. This type of system is difficult to configure and troubleshoot, particularly if the system is installed in a large building with dozens or even hundreds of doors. Further, a vast quantity of copper wiring is required to connect the controller to the readers, locks, door contacts, and request-to-exit devices at each door, sometimes over very long runs, which increases the both the material cost and labor cost associated with the installation of such systems.
More recently, Power over Ethernet (PoE) systems have emerged in which the access control panel is mounted at the door and a single Category 5 (Cat 5) network cable is pulled to the access control panel at the door. The reader, lock, door contact, request-to-exit device, etc. are all connected directly to the access control panel, which is a PoE device, via short runs of copper wire, thereby eliminating the multiple runs of wiring from the central server to each door. Advantageously, decisions are made at the access control panel, and as such each door may continue to operate even if communication with the server is not possible. Communication between the central server and the access control panel is required only during initial configuration, and to update firmware or modify a set of access control rules, etc. Of course, each access control panel includes on-board memory for storing an event log, which may be dumped to the central server according to predetermined criteria.
The main disadvantage that is associated with PoE systems is related to the need to provide an access control panel at each door. Firstly, the access control panel adds to the number of system components that has to be installed at every door, which increases both the material cost and the labor cost of installing this type of system. Further, there may not be a suitable location for installing all of the components of this type of system at every door, and even if suitable locations can be found for all of the components, it is unlikely that the layout can be standardized for a large number of doors. Two types of systems have emerged that are based on this general architecture, and which differ primarily with respect to the placement of the access control panel at the door.
In the first type of system the access control panel is incorporated within the housing of the reader. Unfortunately, several significant disadvantages are associated with this approach. A first disadvantage is that since the decision-making components of the access control panel must be accommodated within the reader housing, the readers are necessarily larger and bulkier compared to the sleeker design that is available in the reader-only format. Even so, due to the limited amount of space that is available within the housing, on-board diagnostic systems for detecting the state of inputs, outputs, communication ports and so forth are virtually non-existent. In order to trouble shoot this type of system the reader must be removed from the wall, so as to allow the technician to gain access to the wires and connections inside the housing. A second and perhaps more serious disadvantage is that the reader, and therefore also the access control panel, is necessarily disposed on the secured side of the door, which makes it susceptible to being tampered with. Even without knowledge about how a specific system works, it is possible for an individual to remove the reader housing and cause the access control panel to unlock the door merely by trial and error. Thus, in order to make the door truly secure it is necessary to add a separate module to the system, which is placed on the non-secured side of the door for controlling the lock mechanism of the door. Of course, this solution adds extra wiring, requires additional components, and largely defeats the purpose of providing an all-in-one reader/controller design.
In the second type of system the access control panel is mounted within a dedicated enclosure. Of course, the installer must find a suitable place to mount the enclosure at each doorway, which often winds up being within the space above the ceiling. Unfortunately, positioning the access control panel within the ceiling space leads to a number of disadvantages. Firstly, it is difficult for a technician to trouble shoot the access control panel since it is located out of reach and within a dark and dusty space with little room to work in. The technician will likely need to balance on a ladder and use a work light during troubleshooting. Secondly, if the access control panel is installed within the ceiling space then the dedicated enclosure may need to be fire rated. It is yet another disadvantage that often there is no space above the ceiling, which makes it problematic to find a suitable location to mount the access control panel. In such cases it may be necessary to mount the access control panel in plain sight, which is aesthetically unappealing, or back in an electrical room, which defeats the purpose of the PoE product. Furthermore, since each doorway may have associated therewith a reader, a door contact, an electronic lock, a request-to-exit device and a separate access control panel, the amount of circuitry that is involved with this system and the power requirements thereof is relatively high.
It would therefore be advantageous to provide a method and system that overcomes at least some of the above-mentioned limitations of the prior art.